Access to control on parent dialog

[Murray Bilker]

I have been trying to add a new string to a combobox control on a parent dialog from one of it's children. I use the following to get a pointer to the parent dialog;

CParent* pParent; // in the header file
pParent = (CParent*) this->GetOwner(); // In the cpp file

I can read the parents variables in the child like this;

int nNumVar = pParent->m_NumVar;

I can only update the parents variables from the child with the following code;

((CParent*)pParent->m_NumVar = nNumVar;

Now I need to add a new string in a combobox from the child. The following two examples seem to be correct but don't work. Intellisense shows everything to me and lets me select the methods and the variables and compiles ok.

pParent->GetDlgItem(IDC_COMBOBOX)->AddString(strSomething);
or
((CParent*)pParent)->GetDlgItem(IDC_COMBOBOX)->AddString(strSomething);

Unfortunetly when I run the program I get an assertion error that says the controls m_pWnd value is NULL.

What can I do. Any help or comments will be greatly appreciated.

Murray Bilker murray@philalock.com
Philadelphia Locking Systems Corp

[Masaaki]

Hi.

Try this.
1) (CComboBox*)(GetParent()->GetDlgItem(IDC_COMBOBOX))->AddString(strSomething);

2) Or you can pass CWnd of CComboBox or Dialog as the parameter of
its dialog as the child.

However, 1) is better because of one line.

Hope for help.
-Masaaki Onishi-

[Murray Bilker]

The code you sent;

(CComboBox*)(GetParent()->GetDlgItem(IDC_MANF))->AddString(m_Manf);

doesn't compile. The compiler error is AddString is not a member of CWnd. I re-bracketed the code as shown below;

((CComboBox*)(GetParent()->GetDlgItem(IDC_MANF)))->AddString(m_Manf);

this compiles ok but causes the same error, at run time, that I had before. Your code basically is identical to mine except yours is one line and mine allows me to use the pointer again and again.

I'm sure the solution is simple (like me). Thanks for the try. Maybe we can figure it out.


Murray Bilker murray@philalock.com
Philadelphia Locking Systems Corp

[Masaaki]

Hi.

It works on my progarm.
That is, ComboBox is on the dialog. If I generate another dialog
from the first one, the program added the string to ComboBox on
the first one from the second dialog.

So, check the other stuff.
The relation bet the first dialog and the second one may not
be parent and child(actually pop-up)?
GetParent() is not pointed to the first dialog correctly?

Hope for help.
-Masaaki Onishi-

[Murray Bilker]

You are correct. I was calling the child dialog as a popup. Unfortunetly that is what the program calls for in this case. I changed the way I was getting the pointer to the parent class and that resolved the problem.

Before;

CParent* pParent;
pParent = (CParent*) this->GetOwner(); // Pointed to the frame!

Now;

CView* pParent;
pParent = ((CFrameWnd*)GetOwner())->GetActiveFrame()->GetActiveView();

Thanks for your help.

Murray Bilker murray@philalock.com
Philadelphia Locking Systems Corp